News release

From: Springer Nature

A type of sugar made of four carbon atoms, called erythrulose, has been identified near the centre of the Milky Way galaxy, according to research published in Nature Astronomy. This finding indicates that complex, biologically relevant molecules can form in space and may contribute to the chemical ingredients available for early metabolic and replication processes.

Sugars are important molecules in living systems, helping to provide energy, build important biological structures, and form parts of genetic material. On Earth, erythrulose is commonly found in raspberries and sunless tanning cosmetics. Scientists have long wondered how these molecules first formed on Earth, because experiments show they do not easily form under early Earth conditions. The previous discovery of ribose and glucose in meteorite and asteroid samples has suggested that some sugars may have come from space, but until now, no sugar had been directly detected in the interstellar medium.

Izaskun Jiménez-Serra and colleagues report the detection of erythrulose in a large cloud of gas and dust called G+0.693-0.027, located near the centre of the Milky Way galaxy. They observed the cloud with the Yebes 40-metre and IRAM 30-metre radio telescopes in Spain. The authors identified the sugar by matching signals in the data to the pattern for erythrulose measured in the laboratory, finding 12 matching sets. They also found that erythrulose is at least eight times more abundant in the gas cloud than similar sugars with three carbon atoms, which were not detected in the same location.

The findings suggest that erythrulose can be made from simpler molecules on dust grains in space and may then become part of more complex chemical systems.